The invention concerns a blister strip for receiving medical and/or pharmaceutical and/or food supplement products, comprising a roll-up product carrier that can be divided into individual blister sections, the single-web product carrier having, one behind the other in its direction of transport F, individual nests defining the division T of the blister strip for receiving single products, as well as a film-like cover for closing the nests, such that each product is arranged in sealed form within one nest.
Blister strips of this kind are used in particular in the manufacture of packs individual to the patient (patient-individual packs). Such packs can be made manually or in automated fashion. In the process, from individual rolled-up blister strips which are preferably each provided with one product type, sections with a single product or several products are unrolled, separated from the blister strip and positioned on a substrate and, if necessary, attached e.g. by gluing or the like. Usually, the blister strip is arranged in sandwich fashion between the substrate and a cover element. The cover element has openings through which the nests at least partially protrude. The substrate is provided with perforations in the region of the products, so that, when the products are removed, the products are pushed through the film-like cover of the blister strip and through the partially weakened material of the substrate by exerting pressure on the nests.
Known blister strips as described for example in U.S. Pat. No. 6,244,442 B1 are designed individually with a single-stepped nest for each product or each type of product. Thus the blister strips and in particular also the nests designed for receiving the products have different geometries from one product to the next or from one product type to the next, depending on the product geometry. Concretely, for example the nests of tablets differ from those of oblongs or capsules in shape and size. Accordingly, the blister sections of different blister strips each carrying a product have different lengths and/or widths. With reference to an example, this means that a blister strip for product A has nests adapted to product A, while a blister strip for product B which has a geometry different to product A has nests adapted to product B, e.g. the blister sections of the blister strip carrying product A being longer than the blister sections of the blister strip carrying product B. Furthermore, the nests usually have a single, one-stepped holding chamber for each product. This means that the nest or the holding chamber is designed exclusively specifically to the product and in individualized fashion. In other words, the size of the opening for pushing out or emergence of the product from the nest corresponds to the size of the product.
From WO 99/01101 A2 is known e.g. a nest of oval shape in section for blisters, which is higher and wider than a product held in it. The nest has several steps to facilitate pushing a product out of the nest, with a plurality of peripheral shoulders. The plurality of peripheral shoulders is intended to guarantee the effect that, in case of continued pressing against the outer surface of the uppermost shoulder, the nest tends to crumple and the subsequent, lower shoulders are gradually pushed together by buckling. U.S. Pat. No. 4,574,954 is concerned with a blister strip which has lozenge-shaped nests in section which each comprise a single-stepped holding chamber. In addition to the holding chamber which receives the product, each nest is assigned a push-out area which, starting from the cover covering the holding chamber, is located behind the holding chamber.
Known blister strips are, for various reasons, disadvantageous to handle both during preferably automatic mounting on a substrate and when pushing the product out of the nest. Due to the different geometries of the blister strips or blister sections, automated mounting is possible only with considerable expenditure on measurement and control. In other words, the mounting head of an automatic mounting machine must in each case control individual collection positions for the blister sections separated from the blister strip. This leads to an increased mounting time as well as an increase in the number of mounting errors, which is to be avoided in the manufacture of patient-individual packs. Furthermore, the different geometries of the nests require corresponding adaptation in particular of the cover elements. To be more precise, individual nest sizes require individual openings or punched-out areas in the cover elements, which leads to an increased number of cover element formats. In addition to the extra costs for the different cover elements, there is also a logistics problem, namely stocking the different cover element formats in the region of the automatic mounting machines. A further problem of product-specific, individualized nest sizes lies in that small products are also assigned to only a small nest. The result is that, owing to the small contact pressure area, when the products are pushed out of the nests an increased effort is necessary, which cannot be applied by all users/patients. Also, due to the fact that the products in the known nests correspond to the size of the opening, it is made more difficult to push them out because the cover closing the nests has a high tension or holding force which must be overcome. This tension or holding force is all the greater, the smaller the cross-section spanned or the opening spanned. They are also made more difficult to push out by the fact that the strip material for the blister strip is thicker, the smaller the nest. A further drawback of the known blister strips lies in that within the nests there are large free spaces not filled by the products, so that there may be insufficient shelf life of the products due to trapped air.